CA1151694A - Gliding ring - Google Patents
Gliding ringInfo
- Publication number
- CA1151694A CA1151694A CA000343215A CA343215A CA1151694A CA 1151694 A CA1151694 A CA 1151694A CA 000343215 A CA000343215 A CA 000343215A CA 343215 A CA343215 A CA 343215A CA 1151694 A CA1151694 A CA 1151694A
- Authority
- CA
- Canada
- Prior art keywords
- airfoil
- recited
- angle
- gliding body
- annular
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C39/00—Aircraft not otherwise provided for
- B64C39/06—Aircraft not otherwise provided for having disc- or ring-shaped wings
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- Engineering & Computer Science (AREA)
- Aviation & Aerospace Engineering (AREA)
- Toys (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
APPLICATION FOR UNITED STATES PATENT
GLIDING RING
Abstract of the Disclosure A gliding ring toy comprised of an annular airfoil angled in order to compensate for air downwash effects and to balance the aerodynamic lift, fore and aft, in gliding flight.
GLIDING RING
Abstract of the Disclosure A gliding ring toy comprised of an annular airfoil angled in order to compensate for air downwash effects and to balance the aerodynamic lift, fore and aft, in gliding flight.
Description
;l~S1694 ~ Background of the Invention 12 1. Field of the Invention:
13 This invention relates ~o amusement devices or 14¦ toys, and, more specifically, aerial flying discs ana ring devices.
16 2. Prior Ar~o 17 There have been numerous prior aerial flying discs 18 and rings. Some of these are listed below~ .
20U. S. Patent No. 3,359,678 - Headrick 21~. S. Patent No~ 3,724,122 - Gillespie 22These patents deal with flying discs.
24 U. S. Patent No. 2,126,245 - Darby U. S. Patent No. 3,828,466 - Geiger 26 U. S. Patent No. 3,939,602 - 8urke & Meyers 27 U. S. Design Patent D241,565 - Molenaar 28 These patents deal with flying discs which include 29 one or more perforations in their surface.
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, ; _ I ~lS169 1 U. S. Patent NoO 708,519 - Bradshaw
13 This invention relates ~o amusement devices or 14¦ toys, and, more specifically, aerial flying discs ana ring devices.
16 2. Prior Ar~o 17 There have been numerous prior aerial flying discs 18 and rings. Some of these are listed below~ .
20U. S. Patent No. 3,359,678 - Headrick 21~. S. Patent No~ 3,724,122 - Gillespie 22These patents deal with flying discs.
24 U. S. Patent No. 2,126,245 - Darby U. S. Patent No. 3,828,466 - Geiger 26 U. S. Patent No. 3,939,602 - 8urke & Meyers 27 U. S. Design Patent D241,565 - Molenaar 28 These patents deal with flying discs which include 29 one or more perforations in their surface.
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, ; _ I ~lS169 1 U. S. Patent NoO 708,519 - Bradshaw
2 ~ S. Patent ~o. 3,580,580 ~ Wark &
Schladermundt 4 U. SO Patent No. 3,765,122 - English S These patents deal with flying ringsO
6 A common feature of the patents listed above is that 7 they all include one or more circular rims, flanges, or lips 8 which are oriented generally perpendicular to the initial path of flight. For example, the Bradshaw patent shows a lip, perpendicular to the plane of the ring, at the inner _ _ _ perimeter of the ring, while the English patent shows a very similar lip on the outer perimeter of the ring. The Wark 34 patent shows lips on both the inner and outer perimeters and although these lips are not perpendicular to the plane, they are very nearly so and thus have a similar aerodynamic 17 effect. These iips serve to stabilize the flight by 18 capturing air below the device in a manner analogous to a 19 parachute. However, they contribute a substantial increase in aerodynamic drag which greatly limits the range and 21 duration of flight.
22 It is clear from reading the disclosures of the 23 Bradshaw, Wark and English patents that they all attempted to dispense with these lips, but were unable to achicve 225 stable flight without them. Bradshaw states at column 2, 26 lines 59 - 62, that his central opening maintains the quoit 27 in an upright position, which result cannot be secured with 28 so light a quoit when the flange is omitted~
Schladermundt 4 U. SO Patent No. 3,765,122 - English S These patents deal with flying ringsO
6 A common feature of the patents listed above is that 7 they all include one or more circular rims, flanges, or lips 8 which are oriented generally perpendicular to the initial path of flight. For example, the Bradshaw patent shows a lip, perpendicular to the plane of the ring, at the inner _ _ _ perimeter of the ring, while the English patent shows a very similar lip on the outer perimeter of the ring. The Wark 34 patent shows lips on both the inner and outer perimeters and although these lips are not perpendicular to the plane, they are very nearly so and thus have a similar aerodynamic 17 effect. These iips serve to stabilize the flight by 18 capturing air below the device in a manner analogous to a 19 parachute. However, they contribute a substantial increase in aerodynamic drag which greatly limits the range and 21 duration of flight.
22 It is clear from reading the disclosures of the 23 Bradshaw, Wark and English patents that they all attempted to dispense with these lips, but were unable to achicve 225 stable flight without them. Bradshaw states at column 2, 26 lines 59 - 62, that his central opening maintains the quoit 27 in an upright position, which result cannot be secured with 28 so light a quoit when the flange is omitted~
3 32 / ~?
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:~S1694 . ..
1 Wark states at column 2, lines 4 - 6, that he utilizes 2 ¦ an outer flange and an inner flange, both of which 3 ¦ contribute to the lift of the aerial disc~ as well as its 41 stability in flightu He provides ribs or beads at the lower S I edges of these flangesO At column 2, lines 18 - 20, he 6 ¦ maintains that these ribs or beads have a stabilizing effect ~¦ during the flight and the outer rib, particularly, does have 81 the ability to hold the rear section at its chosen flight 9¦ angle of attack. He states further in the same column, ~¦ lines 24 - 25, that it has been found that if the outer 11¦ annular rib is omitted the rear edge of the spinning device 12 ¦ tends to rise.
13¦ English states at column 2, lines 62 - 68, that if his 14 circular shaped deflector surface 21 that slopes downwardly ~5¦ and inwardly towards the central opening was merely flat and 16¦ coplanar with his outer ring portion 19 then the vast 17¦ majority of the mass of air of the air sheet would slip over 18 ¦ the top of the toy and not be able to boost up the toy ~91 trailing edge. As a result, the toy leading edge would soon 201 tilt upwardly and its flight would become stalled. At 21 ¦ column 3 lines 29 - 33 he states that the width-to-height 22¦ ratio may vary within an optimum performance range from 1:
231 1/16 (W:hl) and 1: 1~2 (W:h2). If the ratio is beyond this 24¦ range to one side ~e.g. 1: 1/17) then the toy will tend to 251 stall in flight and topple. In this latter statement 26 English is referring to the ratio of the radial width of the 27¦ ring to the axial height of the rim, and if this ratio is 28 too great--meaning that the rim is too small--an unstable 29 flight will result.
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1151~-94 1¦ Rodgers, uO SO Patent No. 4,104,822, designed a flying 2¦ ring which has no lip per se, however, it employs a blunt, 31 thick cross-section which has drag properties somewhat 41 similar to a lipo However, Rodgers does state that the lift 5¦ characteristics of his device must be limited in order to 61 limit the possibility of it rolling (banking) to one side 7 and falling to the ground.
8 Two other prior patents are also noted:
9 U. S. Yatent No. 1,986,937 - MacGregor U. S. Patent No. 1,991,689 - McClintock 11 These two patents relate to heavy steel quoits which 12 are intended to be pitched, like horseshoes, at a stake 13 projecting from the ground. Despite their relatively 14 streamlined appearance, they cannot be classed as aerial toys (gliding bodies). This is because their ratio of 16 weight to lifting area is so high that their calculated 17 minimum speed to sustain a gliding level flight is in excess 18 of 150 feet per second (112 MPH). This is more than three 19 times the velocity of 38 FPS which is attained by aerial flying-saucer toys in normal use.
21 The present inventor sought to develop a new type of 22 circular aerial toy which was capable of exceptionally long-23 range level flights. This necessitated a thin, streamlined, 24 low drag airfoil free of excess thickness, lips, flanges or rims and in a configuration which balanced the aerodynamic 26 lift at the center of gravity in order to achieve a straight 27 flight--something which had eluded all known previous 28 inventors of circular aerial toysO
29 ~
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.' .. _ ' ' ' ' :5;
:~S1694 . ..
1 Wark states at column 2, lines 4 - 6, that he utilizes 2 ¦ an outer flange and an inner flange, both of which 3 ¦ contribute to the lift of the aerial disc~ as well as its 41 stability in flightu He provides ribs or beads at the lower S I edges of these flangesO At column 2, lines 18 - 20, he 6 ¦ maintains that these ribs or beads have a stabilizing effect ~¦ during the flight and the outer rib, particularly, does have 81 the ability to hold the rear section at its chosen flight 9¦ angle of attack. He states further in the same column, ~¦ lines 24 - 25, that it has been found that if the outer 11¦ annular rib is omitted the rear edge of the spinning device 12 ¦ tends to rise.
13¦ English states at column 2, lines 62 - 68, that if his 14 circular shaped deflector surface 21 that slopes downwardly ~5¦ and inwardly towards the central opening was merely flat and 16¦ coplanar with his outer ring portion 19 then the vast 17¦ majority of the mass of air of the air sheet would slip over 18 ¦ the top of the toy and not be able to boost up the toy ~91 trailing edge. As a result, the toy leading edge would soon 201 tilt upwardly and its flight would become stalled. At 21 ¦ column 3 lines 29 - 33 he states that the width-to-height 22¦ ratio may vary within an optimum performance range from 1:
231 1/16 (W:hl) and 1: 1~2 (W:h2). If the ratio is beyond this 24¦ range to one side ~e.g. 1: 1/17) then the toy will tend to 251 stall in flight and topple. In this latter statement 26 English is referring to the ratio of the radial width of the 27¦ ring to the axial height of the rim, and if this ratio is 28 too great--meaning that the rim is too small--an unstable 29 flight will result.
32 / ..
1151~-94 1¦ Rodgers, uO SO Patent No. 4,104,822, designed a flying 2¦ ring which has no lip per se, however, it employs a blunt, 31 thick cross-section which has drag properties somewhat 41 similar to a lipo However, Rodgers does state that the lift 5¦ characteristics of his device must be limited in order to 61 limit the possibility of it rolling (banking) to one side 7 and falling to the ground.
8 Two other prior patents are also noted:
9 U. S. Yatent No. 1,986,937 - MacGregor U. S. Patent No. 1,991,689 - McClintock 11 These two patents relate to heavy steel quoits which 12 are intended to be pitched, like horseshoes, at a stake 13 projecting from the ground. Despite their relatively 14 streamlined appearance, they cannot be classed as aerial toys (gliding bodies). This is because their ratio of 16 weight to lifting area is so high that their calculated 17 minimum speed to sustain a gliding level flight is in excess 18 of 150 feet per second (112 MPH). This is more than three 19 times the velocity of 38 FPS which is attained by aerial flying-saucer toys in normal use.
21 The present inventor sought to develop a new type of 22 circular aerial toy which was capable of exceptionally long-23 range level flights. This necessitated a thin, streamlined, 24 low drag airfoil free of excess thickness, lips, flanges or rims and in a configuration which balanced the aerodynamic 26 lift at the center of gravity in order to achieve a straight 27 flight--something which had eluded all known previous 28 inventors of circular aerial toysO
29 ~
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115~ti9~
SUM~ARY OE` THE INVENTION
_ _ _ The present invention consists of a thin, lightweight, streamlined ring which can be thrown with a spin~ing action and caught in a manner similar to other circular aerial toys, but is capable of dramatically longer flights than these prior devices. A unique feature of the present invention is the small airfoil-angle. This balances the center of lift at the center of gravity and provides for a straight, stable flight without resorting to the high drag configurations of all known prior devices in this category.
Broadly speaking, therefore, the present invention provides a qliding body comprising; an annular airfoil defined by; an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to the axis of revolution, an inner and outer perimeter, a reference extended chord line, passing through the inner and outer perimeters, the annular airfoil configured such that at least a portion of the annular air-foil has a negative airfoil-angle relative to the reference plane, so that, at least in the portion, the outer perimeter of the annulus is lower than the inner perimeter of the annulus when the projected reference plane is horizontal and the body is oriented for proper flight, with the upper surface uppermost; thereby compensating for air downwash and balancing the lift fore and aft in the gliding body, the annular airfoil having a stream-lined cross-section in order to present low aerodynamic drag to a flow of air which is generally parallel to the reference plane, the annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below lOO feet per second.
sd/ ~ -5-~S1694 Il Brief Description o _ the Drawin~s 2 Fi~ure 1 is a cutaway isometric view of the preferred 31 embodiment of the present inventionO
41 Figure lA is an elevational sectional view of a portion S¦ of the structure shown in Figure 1 taken along line A-A in 6¦ the direction of the arrows.
~¦ Figure 2 is a cross-section of the preferred embodiment 8¦ which illustrates the path of the airflow during flight.
91 Figure 3 is a cross-section of a portion of an o¦ alternative airfoil which is cushioned for greater safety.
11¦ Figure 4 is a cross-section of another alternative 121 cushioned airfoil. , ~31 Figure 5 is an isometric view of an alternative ring 14 ¦ configuration in which only portions of the ring have an 15 ¦ angled airfoil.
16 ¦ Figure 6 is an isometric view of another alternative 17 ¦ ring configuration in which the desired angle of the airfoil 18 ¦ is achieved in two portions of the ring by smoothly bending -22 he r ing to a saddle shape.
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~S1694 1 I Detailed Description of the Invention I
2 ¦ Figure l is a cutaway isometric view of the preferred 3 1 embodiment of the invention. It consists of a thin annular 4 ¦ airfoil l, symmetrical around an axis of revolution 2, and S ¦ having a projected plane which is depicted by lines 6. The 6 ¦ projected plane 6 is, of course, perpendicular to the axis 7 ' of revolution 2. The airfoil has an upper surface 9 and a ~¦ lower surface 10~ The leading and trailing edges of the 9 ¦ airfoil are defined by the outer perimeter 3 and the inner 10¦ perimeter 4. Extended chord lines 5 pass through these 11¦ perimeters and describe the airfoil-angle 7, which is 12¦ measured relative to the projected plane 6 of the annulus.
1~¦ In the present invention this airfoil-angle 7 is always 14¦ negative, that is the outer perimeter 3 is lower than the lS¦ inner perimeter 4 when the projected plane 6 of the annulus 16¦ is horizontal and the body is oriented for proper flight, 17¦ with its upper surface uppermost.
18 ¦ When the extended chord lines 5 are extended radially 19¦ inwards to their point of intersection 8 on axis 2, they f 201 form the upper conical surface of an imaginary right 211 circular cone. Revolution of the chord length of extended 22 chord line 5 about axis 2 defines the angled surface of a 23 frustrum of a cone. In Figures 1 and lA, airfoil-angle 7 is 24 exaggerated for the sake of clarity. It is noted in Figure 25 lA that the extended chord line 5 passing through the outer 26 and inner perimeters 3 and 4 lies above the lower surface 27 which in the illustrated embodiment is straight.
28 The present inventor first experimented with a thin 29 ring which was flat~ In other words, angle 7 was zero.
30 When thrown with a right-handed backhand throw~ so that the _.
- , " .
~L~S1~4 1 ¦ ring was spinning clockwise when viewed from above, this 2 ¦ flat ring would always bank to the left and fall to the 3 I ground. When thrown by a forehand throw, with counter-4 ¦ clockwise rotation, the ring banked to the right and again
115~ti9~
SUM~ARY OE` THE INVENTION
_ _ _ The present invention consists of a thin, lightweight, streamlined ring which can be thrown with a spin~ing action and caught in a manner similar to other circular aerial toys, but is capable of dramatically longer flights than these prior devices. A unique feature of the present invention is the small airfoil-angle. This balances the center of lift at the center of gravity and provides for a straight, stable flight without resorting to the high drag configurations of all known prior devices in this category.
Broadly speaking, therefore, the present invention provides a qliding body comprising; an annular airfoil defined by; an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to the axis of revolution, an inner and outer perimeter, a reference extended chord line, passing through the inner and outer perimeters, the annular airfoil configured such that at least a portion of the annular air-foil has a negative airfoil-angle relative to the reference plane, so that, at least in the portion, the outer perimeter of the annulus is lower than the inner perimeter of the annulus when the projected reference plane is horizontal and the body is oriented for proper flight, with the upper surface uppermost; thereby compensating for air downwash and balancing the lift fore and aft in the gliding body, the annular airfoil having a stream-lined cross-section in order to present low aerodynamic drag to a flow of air which is generally parallel to the reference plane, the annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below lOO feet per second.
sd/ ~ -5-~S1694 Il Brief Description o _ the Drawin~s 2 Fi~ure 1 is a cutaway isometric view of the preferred 31 embodiment of the present inventionO
41 Figure lA is an elevational sectional view of a portion S¦ of the structure shown in Figure 1 taken along line A-A in 6¦ the direction of the arrows.
~¦ Figure 2 is a cross-section of the preferred embodiment 8¦ which illustrates the path of the airflow during flight.
91 Figure 3 is a cross-section of a portion of an o¦ alternative airfoil which is cushioned for greater safety.
11¦ Figure 4 is a cross-section of another alternative 121 cushioned airfoil. , ~31 Figure 5 is an isometric view of an alternative ring 14 ¦ configuration in which only portions of the ring have an 15 ¦ angled airfoil.
16 ¦ Figure 6 is an isometric view of another alternative 17 ¦ ring configuration in which the desired angle of the airfoil 18 ¦ is achieved in two portions of the ring by smoothly bending -22 he r ing to a saddle shape.
2265 / ' .
32 / ~
o 6 -- - .
~S1694 1 I Detailed Description of the Invention I
2 ¦ Figure l is a cutaway isometric view of the preferred 3 1 embodiment of the invention. It consists of a thin annular 4 ¦ airfoil l, symmetrical around an axis of revolution 2, and S ¦ having a projected plane which is depicted by lines 6. The 6 ¦ projected plane 6 is, of course, perpendicular to the axis 7 ' of revolution 2. The airfoil has an upper surface 9 and a ~¦ lower surface 10~ The leading and trailing edges of the 9 ¦ airfoil are defined by the outer perimeter 3 and the inner 10¦ perimeter 4. Extended chord lines 5 pass through these 11¦ perimeters and describe the airfoil-angle 7, which is 12¦ measured relative to the projected plane 6 of the annulus.
1~¦ In the present invention this airfoil-angle 7 is always 14¦ negative, that is the outer perimeter 3 is lower than the lS¦ inner perimeter 4 when the projected plane 6 of the annulus 16¦ is horizontal and the body is oriented for proper flight, 17¦ with its upper surface uppermost.
18 ¦ When the extended chord lines 5 are extended radially 19¦ inwards to their point of intersection 8 on axis 2, they f 201 form the upper conical surface of an imaginary right 211 circular cone. Revolution of the chord length of extended 22 chord line 5 about axis 2 defines the angled surface of a 23 frustrum of a cone. In Figures 1 and lA, airfoil-angle 7 is 24 exaggerated for the sake of clarity. It is noted in Figure 25 lA that the extended chord line 5 passing through the outer 26 and inner perimeters 3 and 4 lies above the lower surface 27 which in the illustrated embodiment is straight.
28 The present inventor first experimented with a thin 29 ring which was flat~ In other words, angle 7 was zero.
30 When thrown with a right-handed backhand throw~ so that the _.
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~L~S1~4 1 ¦ ring was spinning clockwise when viewed from above, this 2 ¦ flat ring would always bank to the left and fall to the 3 I ground. When thrown by a forehand throw, with counter-4 ¦ clockwise rotation, the ring banked to the right and again
5 I fell to the ground~
6 The flat ring was constructed of a soft thin aluminum7 I sheet permitting experiments with a variety of bends and 81 deformations of the ring in an effor~ to achieve a straight 91 level flight. It was discovered that when the ring was 10¦ formed in a slightly conical configuration, with the correct 11¦ airfoil-angle 7, a beautiful straight and level flight was =_= I
12 ¦ achieved. Furthermore, because of the thin, low drag form ~31 of the ring, great distances were achieved with very little 14¦ effort. A genuine breakthrough in flight performance had ~51 been achieved. Here was a ring which achieved stable flight 16¦ without the high-drag rims or flanges of previous rings 17 (such as the rings of the Bradshaw, Wark and English 18¦ patents).
19¦ These experiments also revealed that if the airfoil-angle 7 was too slight the ring would always bank to the 21¦ left (for.a level throw with the previously described 22 ¦ clockwise rotation) and if the airfoil-angle 7 was too 231 great, the ring would bank to the right.
241 Subsequently, the inventor embarked on a series of 251 experiments with plastic rings to determine the optimum 26¦ airfoil-angle 7 and also the optimum airfoil section.
27 Purely analytical studies of low Reynold's number drag were 28¦ also employed to select the best inside and outside 29 diameters. The plastic rings were machined on a lathe and _ then vacuum formed under heat to establish the airfoil-31 angle.
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, , . . . _ ~X~;94 1 The experiments with the plastic rings covered airfoil-2 ¦ angles of from zero to three degrees and a variety of 3 I airfoil sections and cambersO Eventually an ogival section 4 with a circular arc top and a straight bottom, was selected 5 I for minimum dragO With this section, the optimum airfoil-61 angle 7, for straight level flight, was found to be 1.5
12 ¦ achieved. Furthermore, because of the thin, low drag form ~31 of the ring, great distances were achieved with very little 14¦ effort. A genuine breakthrough in flight performance had ~51 been achieved. Here was a ring which achieved stable flight 16¦ without the high-drag rims or flanges of previous rings 17 (such as the rings of the Bradshaw, Wark and English 18¦ patents).
19¦ These experiments also revealed that if the airfoil-angle 7 was too slight the ring would always bank to the 21¦ left (for.a level throw with the previously described 22 ¦ clockwise rotation) and if the airfoil-angle 7 was too 231 great, the ring would bank to the right.
241 Subsequently, the inventor embarked on a series of 251 experiments with plastic rings to determine the optimum 26¦ airfoil-angle 7 and also the optimum airfoil section.
27 Purely analytical studies of low Reynold's number drag were 28¦ also employed to select the best inside and outside 29 diameters. The plastic rings were machined on a lathe and _ then vacuum formed under heat to establish the airfoil-31 angle.
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, , . . . _ ~X~;94 1 The experiments with the plastic rings covered airfoil-2 ¦ angles of from zero to three degrees and a variety of 3 I airfoil sections and cambersO Eventually an ogival section 4 with a circular arc top and a straight bottom, was selected 5 I for minimum dragO With this section, the optimum airfoil-61 angle 7, for straight level flight, was found to be 1.5
7¦ degrees for a 3.~ ounce ring of 11.75 inches outside
8 diameter and 1.75 inches chord length.
91 Subseguent to these discoveries the following lO¦ analytical basis for the airfoil-angle was developed by the 1l¦ inventor.
I ¦ It is believed that the unique function of the airfoil-13¦ angle 7 is to balance lift between the forward and aft areas 14¦ of the ring in order to achieve superimposition of the 15¦ center of lift and the center of gravity and thus achieve 16¦ straight flight.
17 ¦ Referring to Figure 2, which is a cross-section of the 18 ¦ invention, note the flow of air depicted by streamlines 20.
l9¦ (In typical level flight, the entire annular plane is 201 oriented at an angle of attack of approximately two degrees 21¦ to the f~ïght path or airflow.) Note that the airflow first 22¦ flows around the forward portion 21 of the airfoil and is 231 deflected downwards by this forward airfoil prior to 241 reaching the aft portion 22 of the annular airfoil. This 2sl downward deflection of the airflow is called "downwash" by 26 aerodynamiciSts and is a factor in the wing and tail 27 interaction of conventional airplanes. Downwash is directly 28 proportional to the lift coeffecient of the forward airfoil.
29 Although the angle of this downwash is also dependant on the _ exact position behind the forward airfoil, aircraft 31 designers generally employ the following formula when 32 calculating downwashO
,,- ~~ ' . , .
~L~L51694 36~CL
l where ~ = downwash angle ~degrees) 41 CL= lift coefficient 51 A= the aspect ratio of the airfoil =
6 span/chord
91 Subseguent to these discoveries the following lO¦ analytical basis for the airfoil-angle was developed by the 1l¦ inventor.
I ¦ It is believed that the unique function of the airfoil-13¦ angle 7 is to balance lift between the forward and aft areas 14¦ of the ring in order to achieve superimposition of the 15¦ center of lift and the center of gravity and thus achieve 16¦ straight flight.
17 ¦ Referring to Figure 2, which is a cross-section of the 18 ¦ invention, note the flow of air depicted by streamlines 20.
l9¦ (In typical level flight, the entire annular plane is 201 oriented at an angle of attack of approximately two degrees 21¦ to the f~ïght path or airflow.) Note that the airflow first 22¦ flows around the forward portion 21 of the airfoil and is 231 deflected downwards by this forward airfoil prior to 241 reaching the aft portion 22 of the annular airfoil. This 2sl downward deflection of the airflow is called "downwash" by 26 aerodynamiciSts and is a factor in the wing and tail 27 interaction of conventional airplanes. Downwash is directly 28 proportional to the lift coeffecient of the forward airfoil.
29 Although the angle of this downwash is also dependant on the _ exact position behind the forward airfoil, aircraft 31 designers generally employ the following formula when 32 calculating downwashO
,,- ~~ ' . , .
~L~L51694 36~CL
l where ~ = downwash angle ~degrees) 41 CL= lift coefficient 51 A= the aspect ratio of the airfoil =
6 span/chord
9 1
10 I Lift coeffecient may be calculated from a flight test as:
11 I
13 (2) CL ~ V2-S
14 ¦ whereW = weight of the flying body (lbs.) 1~ ¦ V = velocity (feet-per-second) l Se = effective liting area of the 16 airfoil (square feet) 18 ¦ In flight, the effective listing area (Se) of the annular 19 1 airoil is that portion of the annulus which is projected 20 1 normal to the flight path. (The sides of the annulus, 21 ¦ parallel to the flight path contribute very little lift.) 22 1 This effective lifting area can be approximated as the mean 23 1 annulus diameter times the sum o the fore and aft chord 24 ¦ lengths:
e ~- OD+ID ~ 2C
27 - (OD~ID)~ C
28 , or 29 Se ~ D 2C
3 where D = mean diameter 3 C - chord length - 10 - ' ,' . .
...... . , , , ~ : , ~ light tests on a typi~al riog showod a vel~city ~f 3~ ~PS
2 and yielded a calculated CL of 0.5. This same ring has an 3~ aspect ratio (A) of 60 Solving equation (l) gives a 41 downwash angle of three degreesO Thus~ the airflow over the 51 aft airfoil area 22 is at a three-degree lower ang1e than 61 the airflow over the forward airfoil area 21.
7 ¦ Clearly, a flat ring (angie 7 = zero) would develop B¦ less lift on the aft portion of the airfoil due to downwash 9 ~ effects. This would cause a pitch-up moment which lO ~ gyroscopic precession would convert to a left-bank (roll), ll¦ in the case of clockwise rotation.
l2 j However, if the ring is formed on a conical plane, as l3 1 shown in Figures l and 2, the downwash effect can be fully l4 ¦ compensated. For example, if the airfoil-angle 7 is 1.5 l5 1 degrees the difference in the angle of attack of the forward 16 ¦ and aft airfoil areas is twice the amount of angle 7, or 17 ~ three degrees, which exactly equals the downwash angle.
l8 Thus, the forward and aft airfoil areas each meet the 19 1 airflow at the same angle of attack and have equal ~and 20 ¦ balanced) lift which provides a straight flight.
21 1 It ib possible to condense and simplify equations (l) 22 ¦ and (2) into a generalized desigr, eq;lation for determining 23 the optimum airfoil-angle:
24 (3) a _ K V ~
26 where a = airfoil-angle 7 I K = a constant 27 V = intended flight velocity 28 D = mean diameter of annulus = OD2ID
30 using measure of 31 W in ounces V in feet per second D in inches then K - 64;000 ~¦ Experience has shown that a flight velocity range of 33 to 2 ¦ 47 FPS is common.
3¦ In this velocity range the range of airfoil angle can 41 be summarized as:
Sl 61 (4) a - K-W
7¦ where K = 45 i 15 lO¦ For example, if W = 3.4 ounces and D = 10", a~ = 1.5 +
ll¦ 0.5 for the above range of flight velocity.
13 (2) CL ~ V2-S
14 ¦ whereW = weight of the flying body (lbs.) 1~ ¦ V = velocity (feet-per-second) l Se = effective liting area of the 16 airfoil (square feet) 18 ¦ In flight, the effective listing area (Se) of the annular 19 1 airoil is that portion of the annulus which is projected 20 1 normal to the flight path. (The sides of the annulus, 21 ¦ parallel to the flight path contribute very little lift.) 22 1 This effective lifting area can be approximated as the mean 23 1 annulus diameter times the sum o the fore and aft chord 24 ¦ lengths:
e ~- OD+ID ~ 2C
27 - (OD~ID)~ C
28 , or 29 Se ~ D 2C
3 where D = mean diameter 3 C - chord length - 10 - ' ,' . .
...... . , , , ~ : , ~ light tests on a typi~al riog showod a vel~city ~f 3~ ~PS
2 and yielded a calculated CL of 0.5. This same ring has an 3~ aspect ratio (A) of 60 Solving equation (l) gives a 41 downwash angle of three degreesO Thus~ the airflow over the 51 aft airfoil area 22 is at a three-degree lower ang1e than 61 the airflow over the forward airfoil area 21.
7 ¦ Clearly, a flat ring (angie 7 = zero) would develop B¦ less lift on the aft portion of the airfoil due to downwash 9 ~ effects. This would cause a pitch-up moment which lO ~ gyroscopic precession would convert to a left-bank (roll), ll¦ in the case of clockwise rotation.
l2 j However, if the ring is formed on a conical plane, as l3 1 shown in Figures l and 2, the downwash effect can be fully l4 ¦ compensated. For example, if the airfoil-angle 7 is 1.5 l5 1 degrees the difference in the angle of attack of the forward 16 ¦ and aft airfoil areas is twice the amount of angle 7, or 17 ~ three degrees, which exactly equals the downwash angle.
l8 Thus, the forward and aft airfoil areas each meet the 19 1 airflow at the same angle of attack and have equal ~and 20 ¦ balanced) lift which provides a straight flight.
21 1 It ib possible to condense and simplify equations (l) 22 ¦ and (2) into a generalized desigr, eq;lation for determining 23 the optimum airfoil-angle:
24 (3) a _ K V ~
26 where a = airfoil-angle 7 I K = a constant 27 V = intended flight velocity 28 D = mean diameter of annulus = OD2ID
30 using measure of 31 W in ounces V in feet per second D in inches then K - 64;000 ~¦ Experience has shown that a flight velocity range of 33 to 2 ¦ 47 FPS is common.
3¦ In this velocity range the range of airfoil angle can 41 be summarized as:
Sl 61 (4) a - K-W
7¦ where K = 45 i 15 lO¦ For example, if W = 3.4 ounces and D = 10", a~ = 1.5 +
ll¦ 0.5 for the above range of flight velocity.
12 1 Figures 5 and 6 show two alternate configurations in
13 ¦ which the airfoil-angle 7 is not uniform around the entire
14 ¦ annulus, but only occurs at certain portions of the annulus.
15 ¦ Note that at least a portion of the annulus has a negative
16 ¦ airfoil-angle 7 relative to the projected reference plane 6.
17 ¦ There are two such portions in each of the samples -~
18 ¦ identified as 50 and 60 in Figures 5 and 6, respectively.
19 ¦ Note that in these portions 50 and 60 the outer perimeter of
20 ¦ the annulus is lower than the inner perimeter of the annulus
21 ¦ when the projected reference plane 6 is horizontal and the
22 ¦ body is oriented for proper flight, with the upper surface 3 ¦ uppermost. Figure 5 illustrates a configuration which is 25 ¦ sharply bent in two places 51 while Figure 6 illustrates a I gradually bent area 61 which forms the plane of the annulus 276 ¦ into a saddle shapeO
¦ Due to the rotation of the ring there is an averaging 28 ¦ effect and the angled portions will still balance downwash I effects. ~owever, this balance is being performed by a fraction of the total area, thus greater angle is required.
3l The required angle may be compu~ed as follows:
.
. . . ' ' ---' ~ . -:
1 ~51~94 2 (5) ~,p St where = angle in the angled portions 5¦ = airfoil angle determined by 61 equation 3 or 4 71 St = totaI airfoil area l S = area of the angled portion of 8 ~ P the airfoil 12 ¦ In the examples of Figures 5 and 6 there are two angled 13 ¦ portions of the airfoil. However it is obvious that these 14¦ same principles are applicable to any number of angled 15¦ portions.
16 ¦ The saddle shape shown in Figure 6 can also be applied 17 ¦ (slightly) in the field to the conical configuration of 18 ¦ Figure l in order to make slight adjustments to the 19 ¦ effective airfoil-angle. For example, for a slow game of 20 ¦ catch the reduced flight velocity will increase the downwash 21¦ angle, as described in equations l and 2. If desired, the 22 ¦ effective airfoil-angle 7 can be easily increased by bending
¦ Due to the rotation of the ring there is an averaging 28 ¦ effect and the angled portions will still balance downwash I effects. ~owever, this balance is being performed by a fraction of the total area, thus greater angle is required.
3l The required angle may be compu~ed as follows:
.
. . . ' ' ---' ~ . -:
1 ~51~94 2 (5) ~,p St where = angle in the angled portions 5¦ = airfoil angle determined by 61 equation 3 or 4 71 St = totaI airfoil area l S = area of the angled portion of 8 ~ P the airfoil 12 ¦ In the examples of Figures 5 and 6 there are two angled 13 ¦ portions of the airfoil. However it is obvious that these 14¦ same principles are applicable to any number of angled 15¦ portions.
16 ¦ The saddle shape shown in Figure 6 can also be applied 17 ¦ (slightly) in the field to the conical configuration of 18 ¦ Figure l in order to make slight adjustments to the 19 ¦ effective airfoil-angle. For example, for a slow game of 20 ¦ catch the reduced flight velocity will increase the downwash 21¦ angle, as described in equations l and 2. If desired, the 22 ¦ effective airfoil-angle 7 can be easily increased by bending
23 1 the ring slightly as shown in Figure 6. A second and 241 opposite example would be in the case of distance 251 competition, where strong throws cause higher flight 26 ¦ velocities and thus a reduction of downwash angle. In this 271 case the ring could be bent slightly upwards (opposite of 28 ¦ Figure 6) to reduce the effective airfoil angle for optimum 29 ¦ high-speed flightO
32 / .
, ~15~694 ~¦ The examp]es of Figures 1 4 all illustrate ogival 21 airfoil sections, which have a circular arc top line and a 31 straight bottom line. The present inventor has studied the 41 low-speed aerodynamic characteristics of a number of airfoil 51 sections and found that this section provides minimum drag, 61 and thus maximum length of flightO However, under special 71 circumstances other airfoil sections could be employed (in 8¦ conjunction with the airfoil-angle 7) to still achieve 91 balanced flightO For example, greater camber might be 10¦ preferred for slower and shorter flights, while conversely 11¦ little or no camber (such as a biconvex section) might be 12¦ preferred for very high speed, long distance flights.
13 ¦ If the airfoil section lacks fore and aft symmetry, the 14 1 optimum airfoil-angle 7 may be slightly modified. For 15 1 example, an experiment was conducted on a ring having an 16 ¦ airfoil section which had its greatest thickness close to 17 ¦ the inside perimeter, rather than midway as is shown in 18 ¦ Figures l through 4. This ring was found to require 19 ¦ slightly less airfoil-angle than rings having an ogival 20 ¦ airfoil. It is believed that, for a given angle of attack, 21 ¦ greater lift is developed when the thicker part of the 22 I section is the leading-edge than when it is trailinq. This, 23 ¦ in itself, partially compensates for downwash effects and
32 / .
, ~15~694 ~¦ The examp]es of Figures 1 4 all illustrate ogival 21 airfoil sections, which have a circular arc top line and a 31 straight bottom line. The present inventor has studied the 41 low-speed aerodynamic characteristics of a number of airfoil 51 sections and found that this section provides minimum drag, 61 and thus maximum length of flightO However, under special 71 circumstances other airfoil sections could be employed (in 8¦ conjunction with the airfoil-angle 7) to still achieve 91 balanced flightO For example, greater camber might be 10¦ preferred for slower and shorter flights, while conversely 11¦ little or no camber (such as a biconvex section) might be 12¦ preferred for very high speed, long distance flights.
13 ¦ If the airfoil section lacks fore and aft symmetry, the 14 1 optimum airfoil-angle 7 may be slightly modified. For 15 1 example, an experiment was conducted on a ring having an 16 ¦ airfoil section which had its greatest thickness close to 17 ¦ the inside perimeter, rather than midway as is shown in 18 ¦ Figures l through 4. This ring was found to require 19 ¦ slightly less airfoil-angle than rings having an ogival 20 ¦ airfoil. It is believed that, for a given angle of attack, 21 ¦ greater lift is developed when the thicker part of the 22 I section is the leading-edge than when it is trailinq. This, 23 ¦ in itself, partially compensates for downwash effects and
24 ¦ lessens the required airfoil-angle for straight flight.
25 ¦ However, because this particular airfoil presented its
26 ¦ thinnest portion at the outside perimeter it was found to be
27 ¦ more easily damaged than the ogival section; thus it is not
28 ¦ preferred.
29 ¦ In all cases, however, the airfoil should be quite thin
30 if a long sustained flight is desiredO At these relatively
31 low Reynold's numbers, drag is essentia]ly proportional to
32 thickness. - 14 -. .
. , . . . - _ - :
~15~6g~
~¦ Flanges at the inner perimeter, such as that employed 2¦ by Bradshaw cause dragO Thus, no f~anges are employed at 3I the inner perimeter of the present invention; the vertical 41 distance between the highest and lowest portion at the inner 5 ¦ perimeter of the gliding ring in accordance with this 61 invention is less than the maximum thickness of the airfoil.
7¦ Figures 3 and 4 illustrate cushioned airfoils intended 8 ¦ for great safety and comfort in catchingO In Figure ~ the 91 airfoil edges 30 are made from a soft material, such as o¦ rubber or thermoplastic elastomer. The components may be 11¦ molded separate~y and bonded together or the elastomer 30 12 may be molded directly onto the structural ring 31. In 13¦ Figure 4 the elastomer 40 is molded over the structural ring 14 ¦ 41. Pins in the mold may be employed to keep the structural 15 ring 41 centered during the process of molding-on the 16 ¦ elastomer 400 Alternatively, the structural ring 41 can be 17 ¦ made with a number of small raised bosses on the upper and 18 ¦ lower surfaces which contact the surface of the elastomer-19 I mold in order to maintain the position of the structural 20 ¦ ring during the elastomer molding process.
21 It ,is also possible to mold the entire airfoil from a 22 flexible material, without the added structural ring.
23 ¦ However, in this case the material must be considerably more 24 ¦ rigid than is required in the versions of Figures 3 and 4.
In some cases it is desirable to texture the surface 26 ¦ (especially the ~pper surface) of the airfoil as shown at 11 27 I in Figure 1. The texture improves grip when throwing and 28 catching. Furthermore, it is believed that texture may 29 enhance lift due to centrifugally-induced airflow caused by the rapid spin during flightO
, . .. .. ....
~S~f~94 . .
I The flight performance of this invention is ~ruly 2 amazing. For example, a ring of Figure 1 was constructed 3 having the following dimensions.
4 Outside diameter 11.75 Airfoil chord length 1.75~
6 Airfoil thickness 0.135"
7 Weight 3.4 ounces 8 Airfoil angle 1.5 degrees 9 The ring flies in an exceptionally flat trajectory and straight flight path. The amazing part of its flight is the Il way it keeps on flying long after everyone has expected it 12 to fall to earth. Many people, including a twelve-year old 13 boy, have been able to throw it farther than 100 yards.
14 While in the foregoing specification embodiments of the invention have been set forth in considerable detail for 16 purposes of making a complete disclosure thereof, it will be 17 apparent to those skilled in the art that numerous changes 18 may be made in certain details without departing from the 22 ¦ spirit a. rinciples of the invention.
2243 / ' 226 / .
/
32 / ~
. - 16 - -'''~
-
. , . . . - _ - :
~15~6g~
~¦ Flanges at the inner perimeter, such as that employed 2¦ by Bradshaw cause dragO Thus, no f~anges are employed at 3I the inner perimeter of the present invention; the vertical 41 distance between the highest and lowest portion at the inner 5 ¦ perimeter of the gliding ring in accordance with this 61 invention is less than the maximum thickness of the airfoil.
7¦ Figures 3 and 4 illustrate cushioned airfoils intended 8 ¦ for great safety and comfort in catchingO In Figure ~ the 91 airfoil edges 30 are made from a soft material, such as o¦ rubber or thermoplastic elastomer. The components may be 11¦ molded separate~y and bonded together or the elastomer 30 12 may be molded directly onto the structural ring 31. In 13¦ Figure 4 the elastomer 40 is molded over the structural ring 14 ¦ 41. Pins in the mold may be employed to keep the structural 15 ring 41 centered during the process of molding-on the 16 ¦ elastomer 400 Alternatively, the structural ring 41 can be 17 ¦ made with a number of small raised bosses on the upper and 18 ¦ lower surfaces which contact the surface of the elastomer-19 I mold in order to maintain the position of the structural 20 ¦ ring during the elastomer molding process.
21 It ,is also possible to mold the entire airfoil from a 22 flexible material, without the added structural ring.
23 ¦ However, in this case the material must be considerably more 24 ¦ rigid than is required in the versions of Figures 3 and 4.
In some cases it is desirable to texture the surface 26 ¦ (especially the ~pper surface) of the airfoil as shown at 11 27 I in Figure 1. The texture improves grip when throwing and 28 catching. Furthermore, it is believed that texture may 29 enhance lift due to centrifugally-induced airflow caused by the rapid spin during flightO
, . .. .. ....
~S~f~94 . .
I The flight performance of this invention is ~ruly 2 amazing. For example, a ring of Figure 1 was constructed 3 having the following dimensions.
4 Outside diameter 11.75 Airfoil chord length 1.75~
6 Airfoil thickness 0.135"
7 Weight 3.4 ounces 8 Airfoil angle 1.5 degrees 9 The ring flies in an exceptionally flat trajectory and straight flight path. The amazing part of its flight is the Il way it keeps on flying long after everyone has expected it 12 to fall to earth. Many people, including a twelve-year old 13 boy, have been able to throw it farther than 100 yards.
14 While in the foregoing specification embodiments of the invention have been set forth in considerable detail for 16 purposes of making a complete disclosure thereof, it will be 17 apparent to those skilled in the art that numerous changes 18 may be made in certain details without departing from the 22 ¦ spirit a. rinciples of the invention.
2243 / ' 226 / .
/
32 / ~
. - 16 - -'''~
-
Claims (22)
1. A gliding body comprising, an annular airfoil defined by;
an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to said axis of revolution, an inner and outer perimeter, a reference extended chord line, passing through said inner and outer perimeters, said annular airfoil configured such that at least a portion of said annular airfoil has a negative airfoil-angle relative to said reference plane, so that, at least in said portion, the outer perimeter of the annulus is lower than the inner perimeter of the annulus when said projected reference plane is horizontal and said body is oriented for proper flight, with said upper surface uppermost; thereby compensating for air downwash and balancing the lift fore and aft in said gliding body, said annular airfoil having a streamlined cross-section in order to present low aerodynamic drag to a flow of air which is generally parallel to said reference plane, said annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below 100 feet per second.
an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to said axis of revolution, an inner and outer perimeter, a reference extended chord line, passing through said inner and outer perimeters, said annular airfoil configured such that at least a portion of said annular airfoil has a negative airfoil-angle relative to said reference plane, so that, at least in said portion, the outer perimeter of the annulus is lower than the inner perimeter of the annulus when said projected reference plane is horizontal and said body is oriented for proper flight, with said upper surface uppermost; thereby compensating for air downwash and balancing the lift fore and aft in said gliding body, said annular airfoil having a streamlined cross-section in order to present low aerodynamic drag to a flow of air which is generally parallel to said reference plane, said annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below 100 feet per second.
2. A gliding body as recited in Claim 1 wherein said annular airfoil is of ogival cross-section.
3. A gliding body as recited in Claim 1 wherein at least a portion of said body has 2 textured surface.
4. A gliding body as recited in Claim 1 wherein said annular airfoil is fabricated from a resilient material.
5. A gliding body as recited in Claim 4 wherein said resilient material is centrally stiffened by a more rigid material.
6. A gliding body as recited in Claim 5 wherein said resilient material is a thermoplastic elastomer and said more rigid material is high-impact thermoplastic.
7. A gliding body as recited in Claim 1 wherein said airfoil-angle is computed from the following formula:
.alpha.p = where .alpha.p = degrees of airfoil angle in those portions of the airfoil which are angled St = total airfoil area S p = area of the angled portions of the airfoil .alpha. = where:
K = 45?15 W = weight of said gliding body in ounces D = mean diameter of annulus in inches
.alpha.p = where .alpha.p = degrees of airfoil angle in those portions of the airfoil which are angled St = total airfoil area S p = area of the angled portions of the airfoil .alpha. = where:
K = 45?15 W = weight of said gliding body in ounces D = mean diameter of annulus in inches
8. A gliding body comprising;
an annular airfoil defined by;
an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to said axis of revolution, an inner and outer perimeter, a reference chord line passing through said inner and outer perimeters, said annular airfoil configured with an airfoil-angle such that the revolution of the chord length of said reference chord line defines the angled surface of a frustrum of a cone, whereby in flight the forward portion of said annular airfoil is at a lower angle of incidence to the flight path than the remainder of said annular airfoil, thereby compensating for air downwash effects from said forward portion and balancing the aerodynamic lift fore and aft in said gliding body, said annular airfoil having a streamlined cross-section in order to present low aerodynamic drag to a flow of air which is generally parallel to said reference plane, said annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below 100 feet per second.
an annular airfoil defined by;
an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to said axis of revolution, an inner and outer perimeter, a reference chord line passing through said inner and outer perimeters, said annular airfoil configured with an airfoil-angle such that the revolution of the chord length of said reference chord line defines the angled surface of a frustrum of a cone, whereby in flight the forward portion of said annular airfoil is at a lower angle of incidence to the flight path than the remainder of said annular airfoil, thereby compensating for air downwash effects from said forward portion and balancing the aerodynamic lift fore and aft in said gliding body, said annular airfoil having a streamlined cross-section in order to present low aerodynamic drag to a flow of air which is generally parallel to said reference plane, said annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below 100 feet per second.
9. A gliding body as recited in Claim 8 wherein said airfoil-angle is determined by the following formula:
.alpha. = where .alpha. = airfoil-angle, degrees K = 45?15 W = weight of said gliding body, ounces D = means diameter of annulus, inches
.alpha. = where .alpha. = airfoil-angle, degrees K = 45?15 W = weight of said gliding body, ounces D = means diameter of annulus, inches
10. A gliding body as recited in Claim 8 wherein said airfoil angle is between 1 and 2 degrees.
11. A gliding body as recited in Claim 8 and having the following dimensions:
Weight = 2 to 4 ounces Mean diameter = 8 to 12 inches Chord length = 1 to 3 inches Thickness = .05 to .20 inches Airfoil angle = 1 to 2 degrees
Weight = 2 to 4 ounces Mean diameter = 8 to 12 inches Chord length = 1 to 3 inches Thickness = .05 to .20 inches Airfoil angle = 1 to 2 degrees
12. A gliding body as recited in Claim 11 having an ogival airfoil section.
13. A gliding body as recited in Claim 12 wherein said body is constructed of high impact thermoplastic material.
14. A gliding body as recited in Claim 12 wherein said body is constructed of a composite of thermoplastic elastomer material and high-impact thermoplastic material.
15. A gliding body as recited in Claim 8 wherein said airfoil angle is determined by the following formula:
where .alpha. = airfoil angle, degrees W = weight of said gliding body, ounces V = intended flight velocity, feet per second D = mean diameter of annulus, inches
where .alpha. = airfoil angle, degrees W = weight of said gliding body, ounces V = intended flight velocity, feet per second D = mean diameter of annulus, inches
16. A gliding body comprising;
an annular airfoil defined by;
an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to said axis of revolution, an inner and outer perimeter, a reference extended chord line, passing through said inner and outer perimeters, said annular airfoil configured such that at least a portion of said annular airfoil has a negative airfoil-angle relative to said reference plane, so that, at least in said portion, the outer perimeter of the annulus is lower than the inner perimeter of the annulus when said projected reference plane is horizontal and said body is oriented for proper flight, with said upper surface uppermost; thereby compensating for air downwash and balancing the lift fore and aft in said gliding body, said annular airfoil having a streamlined cross-section in which the vertical distance between the highest and lowest portions at the inner perimeter is less than the maximum thickness of the airfoil, said annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below 100 feet per second.
an annular airfoil defined by;
an upper and a lower surface, an axis of revolution, a projected reference plane which is normal to said axis of revolution, an inner and outer perimeter, a reference extended chord line, passing through said inner and outer perimeters, said annular airfoil configured such that at least a portion of said annular airfoil has a negative airfoil-angle relative to said reference plane, so that, at least in said portion, the outer perimeter of the annulus is lower than the inner perimeter of the annulus when said projected reference plane is horizontal and said body is oriented for proper flight, with said upper surface uppermost; thereby compensating for air downwash and balancing the lift fore and aft in said gliding body, said annular airfoil having a streamlined cross-section in which the vertical distance between the highest and lowest portions at the inner perimeter is less than the maximum thickness of the airfoil, said annular airfoil having a weight of less than 0.2 ounces per square inch of projected area, thereby permitting a substantially level glide at speeds below 100 feet per second.
17. A gliding body as recited in Claim 16 wherein said annular airfoil is of ogival cross-section.
18. A gliding body as recited in Claim 16 wherein at least a portion of said body has a textured surface.
19. A gliding body as recited in Claim 16 wherein said annular airfoil is fabricated from a resilient material.
20. A gliding body as recited in Claim 19 wherein said resilient material is centrally stiffened by a more rigid material.
21. A gliding body as recited in Claim 20 wherein said resilient material is a thermoplastic elastomer and said more rigid material is high-impact thermoplastic.
22. A gliding body as recited in Claim 16 wherein said airfoil-angle is computed from the following formula:
where .alpha.p = degrees of airfoil angle in those portions of the airfoil which are angled St = total airfoil area Sp = area of the angled portions of the airfoil where:
K = 45?15 W = weight of said gliding body in ounces D = mean diameter of annulus in inches
where .alpha.p = degrees of airfoil angle in those portions of the airfoil which are angled St = total airfoil area Sp = area of the angled portions of the airfoil where:
K = 45?15 W = weight of said gliding body in ounces D = mean diameter of annulus in inches
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US3,992 | 1979-01-16 | ||
| US06/003,992 US4456265A (en) | 1979-01-16 | 1979-01-16 | Gliding ring |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1151694A true CA1151694A (en) | 1983-08-09 |
Family
ID=21708584
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000343215A Expired CA1151694A (en) | 1979-01-16 | 1980-01-08 | Gliding ring |
Country Status (16)
| Country | Link |
|---|---|
| US (1) | US4456265A (en) |
| JP (1) | JPS5599498A (en) |
| AU (1) | AU5451980A (en) |
| BE (1) | BE881184A (en) |
| BR (1) | BR8000246A (en) |
| CA (1) | CA1151694A (en) |
| DE (1) | DE3000758A1 (en) |
| DK (1) | DK18080A (en) |
| ES (1) | ES255192Y (en) |
| FI (1) | FI800127A (en) |
| FR (1) | FR2446661A1 (en) |
| GB (1) | GB2039760B (en) |
| IT (1) | IT8047595A0 (en) |
| LU (1) | LU82086A1 (en) |
| NL (1) | NL8000233A (en) |
| SE (1) | SE441895B (en) |
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| AU2144083A (en) * | 1982-04-29 | 1984-05-24 | Marshall Rushton Blight | Boomerang |
| US4560358A (en) * | 1984-05-10 | 1985-12-24 | Adler Alan John | Gliding ring |
| JPS6239762U (en) * | 1985-08-28 | 1987-03-10 | ||
| US4669996A (en) * | 1985-10-07 | 1987-06-02 | Bershak William P | Recreational flying ring having primary and secondary airfoils |
| GB2193649A (en) * | 1986-08-09 | 1988-02-17 | Littler Gordon Brian Russell | Game apparatus |
| US4854907A (en) * | 1988-01-27 | 1989-08-08 | Holmes Stephen E | "ESU" flying ring |
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| US5816880A (en) * | 1992-01-21 | 1998-10-06 | Forti; William M. | Gyroscopic flying device |
| DE4203286C2 (en) * | 1992-02-03 | 1993-10-21 | Hektor Steinhilber | Flight car |
| US5358440A (en) * | 1994-01-06 | 1994-10-25 | Yu Zheng | Collapsible flying disc |
| US5531624A (en) * | 1994-02-14 | 1996-07-02 | Innova Champion Discs, Inc. | Flying disc |
| US5562512A (en) * | 1994-05-27 | 1996-10-08 | Samelian; John K. | Rescue device |
| US6179737B1 (en) * | 1995-01-09 | 2001-01-30 | Alan J. Adler | Flying disc |
| USD388134S (en) * | 1996-02-28 | 1997-12-23 | Innova Champion Discs, Inc. | Flying disc |
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| US6247989B1 (en) | 1999-04-26 | 2001-06-19 | Richard D. Neff | Secondary lift flying ring |
| US6386997B1 (en) * | 2000-05-06 | 2002-05-14 | Kenneth M. Brown | Ultimate ring toss game |
| US7581500B2 (en) * | 2004-01-30 | 2009-09-01 | Flatau & Vanek, Llc | Payload delivering ring airfoil projectile |
| GB0402910D0 (en) * | 2004-02-11 | 2004-03-17 | Potts Jonathan | Flying disc |
| US20060163424A1 (en) * | 2004-09-16 | 2006-07-27 | Stumphauzer William C Ii | AeroStreamer Flight Kit |
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| US20100304635A1 (en) * | 2009-01-06 | 2010-12-02 | Bershak William P | Material improvements including the addition of a third airfoil to recreational flying ring having primary and secondary airfoils |
| US8353792B2 (en) * | 2010-10-15 | 2013-01-15 | Joe Arroyo | Teardrop ring tossing game |
| US10486835B2 (en) * | 2013-03-12 | 2019-11-26 | William R. Crowe | Centrifugal force amplification method and system for generating vehicle lift |
| US9709069B2 (en) * | 2013-10-22 | 2017-07-18 | Dayspring Church Of God Apostolic | Hybrid drive engine |
| US10118696B1 (en) | 2016-03-31 | 2018-11-06 | Steven M. Hoffberg | Steerable rotating projectile |
| US11712637B1 (en) | 2018-03-23 | 2023-08-01 | Steven M. Hoffberg | Steerable disk or ball |
| USD1006892S1 (en) * | 2023-06-20 | 2023-12-05 | David Laemle | Flying disc |
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| US3029077A (en) * | 1961-05-25 | 1962-04-10 | Transogram Company Inc | Readily assemblable, multiple piece toy targets |
| US3082572A (en) * | 1961-10-05 | 1963-03-26 | Knox Instr Inc | Aerial toy |
| US3312472A (en) * | 1963-07-05 | 1967-04-04 | Robert A Kerr | Throwing disc employing raised aerodynamic sections |
| US3220142A (en) * | 1964-09-04 | 1965-11-30 | Butterfield Floyd | Aerial toy |
| US3565434A (en) * | 1965-10-18 | 1971-02-23 | James F Liston | Boomerang with adjustable-pitch blades |
| US3359678A (en) * | 1965-11-01 | 1967-12-26 | Wham O Mfg Company | Flying saucer |
| US3566532A (en) * | 1967-11-08 | 1971-03-02 | Wilson Henry A | Flying saucer type toy |
| US3545760A (en) * | 1968-01-30 | 1970-12-08 | Wilson Henry A | Combined cap and aerial projector |
| US3838835A (en) * | 1969-02-25 | 1974-10-01 | A Kling | Precessor flying craft |
| US3594945A (en) * | 1969-04-14 | 1971-07-27 | Howard R Turney | Flying toy |
| US3580580A (en) * | 1969-09-24 | 1971-05-25 | John D Wark | Aerial spinning disc |
| US3673732A (en) * | 1970-10-15 | 1972-07-04 | Liotta Alfonso L | Aerial toy |
| US3765122A (en) * | 1970-10-29 | 1973-10-16 | R English | Flying toy |
| US3724122A (en) * | 1971-03-16 | 1973-04-03 | Wham O Mfg Co | Flying saucer |
| US3673731A (en) * | 1971-06-21 | 1972-07-04 | Raphael Farhi | Reversible aerodynamic disc and gyroscopic toy |
| US3742643A (en) * | 1972-05-05 | 1973-07-03 | C Keith | Flying device |
| US3828466A (en) * | 1972-06-22 | 1974-08-13 | E Geiger | Flying saucer |
| US4023805A (en) * | 1974-05-01 | 1977-05-17 | Harry Sherrill | Tricky disk |
| US3939602A (en) * | 1975-05-27 | 1976-02-24 | Marvin Glass & Associates | Circular air glider |
| FR2349495A1 (en) * | 1976-04-29 | 1977-11-25 | Baudchon Christian | Vtol aircraft with circular wing - forces air radially outwards over ring of aerofoil section |
| DE2725383A1 (en) * | 1976-06-07 | 1977-12-15 | Reginald Clucas | METHOD AND DEVICE FOR GENERATING LIFT IN LAND, SEA AND AIRCRAFT VEHICLES |
| US4104822B2 (en) * | 1976-12-03 | 1989-06-27 | Rotating circular airfoil | |
| US4114885A (en) * | 1976-12-10 | 1978-09-19 | Morrow Larry N | Throwing disc |
-
1979
- 1979-01-16 US US06/003,992 patent/US4456265A/en not_active Expired - Lifetime
-
1980
- 1980-01-08 CA CA000343215A patent/CA1151694A/en not_active Expired
- 1980-01-10 DE DE19803000758 patent/DE3000758A1/en active Granted
- 1980-01-10 AU AU54519/80A patent/AU5451980A/en not_active Abandoned
- 1980-01-14 JP JP346080A patent/JPS5599498A/en active Pending
- 1980-01-14 ES ES1980255192U patent/ES255192Y/en not_active Expired
- 1980-01-14 IT IT8047595A patent/IT8047595A0/en unknown
- 1980-01-15 BR BR8000246A patent/BR8000246A/en unknown
- 1980-01-15 NL NL8000233A patent/NL8000233A/en unknown
- 1980-01-15 LU LU82086A patent/LU82086A1/en unknown
- 1980-01-15 FR FR8000829A patent/FR2446661A1/en not_active Withdrawn
- 1980-01-16 FI FI800127A patent/FI800127A/en not_active Application Discontinuation
- 1980-01-16 SE SE8000355A patent/SE441895B/en not_active IP Right Cessation
- 1980-01-16 BE BE0/198992A patent/BE881184A/en unknown
- 1980-01-16 DK DK18080A patent/DK18080A/en unknown
- 1980-01-16 GB GB8001519A patent/GB2039760B/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB2039760A (en) | 1980-08-20 |
| ES255192Y (en) | 1981-11-16 |
| FI800127A (en) | 1980-07-17 |
| SE8000355L (en) | 1980-07-17 |
| NL8000233A (en) | 1980-07-18 |
| AU5451980A (en) | 1980-07-24 |
| GB2039760B (en) | 1983-08-17 |
| DE3000758A1 (en) | 1980-07-24 |
| DK18080A (en) | 1980-07-17 |
| SE441895B (en) | 1985-11-18 |
| FR2446661A1 (en) | 1980-08-14 |
| DE3000758C2 (en) | 1988-09-01 |
| IT8047595A0 (en) | 1980-01-14 |
| JPS5599498A (en) | 1980-07-29 |
| ES255192U (en) | 1981-05-01 |
| BR8000246A (en) | 1980-09-30 |
| BE881184A (en) | 1980-05-16 |
| LU82086A1 (en) | 1980-06-06 |
| US4456265A (en) | 1984-06-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |